The two biggest changes are that the RESTful API ( eAPI ) is now free in both IMC Standard and Enterprise, and IMC Enterprise now comes with the WSM module to manage up to 50 APs included.

If you're looking for more information on IMC you can always check out the product page ( same like as above ) or you can head over to http://www.youtube.com/theimcmanagement which has a bunch of Video tutorials that will help you get up to speed faster.